drivers/xen/xen-pciback/pci_stub.c

   1 /*
   2  * PCI Stub Driver - Grabs devices in backend to be exported later
   3  *
   4  * Ryan Wilson <[email protected]>
   5  * Chris Bookholt <[email protected]>
   6  */
   7
   8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9 #define dev_fmt pr_fmt
  10
  11 #include <linux/module.h>
  12 #include <linux/init.h>
  13 #include <linux/rwsem.h>
  14 #include <linux/list.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/kref.h>
  17 #include <linux/pci.h>
  18 #include <linux/wait.h>
  19 #include <linux/sched.h>
  20 #include <linux/atomic.h>
  21 #include <xen/events.h>
  22 #include <xen/pci.h>
  23 #include <xen/xen.h>
  24 #ifdef CONFIG_XEN_ACPI
  25 #include <xen/acpi.h>
  26 #endif
  27 #include <asm/xen/hypervisor.h>
  28 #include <xen/interface/physdev.h>
  29 #include "pciback.h"
  30 #include "conf_space.h"
  31 #include "conf_space_quirks.h"
  32
  33 #define PCISTUB_DRIVER_NAME "pciback"
  34
  35 static char *pci_devs_to_hide;
  36 wait_queue_head_t xen_pcibk_aer_wait_queue;
  37 /*Add sem for sync AER handling and xen_pcibk remove/reconfigue ops,
  38 * We want to avoid in middle of AER ops, xen_pcibk devices is being removed
  39 */
  40 static DECLARE_RWSEM(pcistub_sem);
  41 module_param_named(hide, pci_devs_to_hide, charp, 0444);
  42
  43 struct pcistub_device_id {
  44         struct list_head slot_list;
  45         int domain;
  46         unsigned char bus;
  47         unsigned int devfn;
  48 };
  49 static LIST_HEAD(pcistub_device_ids);
  50 static DEFINE_SPINLOCK(device_ids_lock);
  51
  52 struct pcistub_device {
  53         struct kref kref;
  54         struct list_head dev_list;
  55         spinlock_t lock;
  56
  57         struct pci_dev *dev;
  58         struct xen_pcibk_device *pdev;/* non-NULL if struct pci_dev is in use */
  59 #ifdef CONFIG_XEN_ACPI
  60         int gsi;
  61 #endif
  62 };
  63
  64 /* Access to pcistub_devices & seized_devices lists and the initialize_devices
  65  * flag must be locked with pcistub_devices_lock
  66  */
  67 static DEFINE_SPINLOCK(pcistub_devices_lock);
  68 static LIST_HEAD(pcistub_devices);
  69
  70 /* wait for device_initcall before initializing our devices
  71  * (see pcistub_init_devices_late)
  72  */
  73 static int initialize_devices;
  74 static LIST_HEAD(seized_devices);
  75
  76 static struct pcistub_device *pcistub_device_alloc(struct pci_dev *dev)
  77 {
  78         struct pcistub_device *psdev;
  79
  80         dev_dbg(&dev->dev, "pcistub_device_alloc\n");
  81
  82         psdev = kzalloc(sizeof(*psdev), GFP_KERNEL);
  83         if (!psdev)
  84                 return NULL;
  85
  86         psdev->dev = pci_dev_get(dev);
  87         if (!psdev->dev) {
  88                 kfree(psdev);
  89                 return NULL;
  90         }
  91
  92         kref_init(&psdev->kref);
  93         spin_lock_init(&psdev->lock);
  94 #ifdef CONFIG_XEN_ACPI
  95         psdev->gsi = -1;
  96 #endif
  97
  98         return psdev;
  99 }
 100
 101 static int pcistub_reset_device_state(struct pci_dev *dev)
 102 {
 103         __pci_reset_function_locked(dev);
 104
 105         if (!xen_pv_domain())
 106                 return xen_reset_device(dev);
 107         else
 108                 return 0;
 109 }
 110
 111 /* Don't call this directly as it's called by pcistub_device_put */
 112 static void pcistub_device_release(struct kref *kref)
 113 {
 114         struct pcistub_device *psdev;
 115         struct pci_dev *dev;
 116         struct xen_pcibk_dev_data *dev_data;
 117
 118         psdev = container_of(kref, struct pcistub_device, kref);
 119         dev = psdev->dev;
 120         dev_data = pci_get_drvdata(dev);
 121
 122         dev_dbg(&dev->dev, "pcistub_device_release\n");
 123
 124         xen_unregister_device_domain_owner(dev);
 125
 126         /* Call the reset function which does not take lock as this
 127          * is called from "unbind" which takes a device_lock mutex.
 128          */
 129         pcistub_reset_device_state(dev);
 130         if (dev_data &&
 131             pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state))
 132                 dev_info(&dev->dev, "Could not reload PCI state\n");
 133         else
 134                 pci_restore_state(dev);
 135
 136         if (dev->msix_cap) {
 137                 struct physdev_pci_device ppdev = {
 138                         .seg = pci_domain_nr(dev->bus),
 139                         .bus = dev->bus->number,
 140                         .devfn = dev->devfn
 141                 };
 142                 int err = HYPERVISOR_physdev_op(PHYSDEVOP_release_msix,
 143                                                 &ppdev);
 144
 145                 if (err && err != -ENOSYS)
 146                         dev_warn(&dev->dev, "MSI-X release failed (%d)\n",
 147                                  err);
 148         }
 149
 150         /* Disable the device */
 151         xen_pcibk_reset_device(dev);
 152
 153         kfree(dev_data);
 154         pci_set_drvdata(dev, NULL);
 155
 156         /* Clean-up the device */
 157         xen_pcibk_config_free_dyn_fields(dev);
 158         xen_pcibk_config_free_dev(dev);
 159
 160         pci_clear_dev_assigned(dev);
 161         pci_dev_put(dev);
 162
 163         kfree(psdev);
 164 }
 165
 166 static inline void pcistub_device_get(struct pcistub_device *psdev)
 167 {
 168         kref_get(&psdev->kref);
 169 }
 170
 171 static inline void pcistub_device_put(struct pcistub_device *psdev)
 172 {
 173         kref_put(&psdev->kref, pcistub_device_release);
 174 }
 175
 176 static struct pcistub_device *pcistub_device_find_locked(int domain, int bus,
 177                                                          int slot, int func)
 178 {
 179         struct pcistub_device *psdev;
 180
 181         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 182                 if (psdev->dev != NULL
 183                     && domain == pci_domain_nr(psdev->dev->bus)
 184                     && bus == psdev->dev->bus->number
 185                     && slot == PCI_SLOT(psdev->dev->devfn)
 186                     && func == PCI_FUNC(psdev->dev->devfn)) {
 187                         return psdev;
 188                 }
 189         }
 190
 191         return NULL;
 192 }
 193
 194 static struct pcistub_device *pcistub_device_find(int domain, int bus,
 195                                                   int slot, int func)
 196 {
 197         struct pcistub_device *psdev;
 198         unsigned long flags;
 199
 200         spin_lock_irqsave(&pcistub_devices_lock, flags);
 201
 202         psdev = pcistub_device_find_locked(domain, bus, slot, func);
 203         if (psdev)
 204                 pcistub_device_get(psdev);
 205
 206         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 207         return psdev;
 208 }
 209
 210 static struct pci_dev *pcistub_device_get_pci_dev(struct xen_pcibk_device *pdev,
 211                                                   struct pcistub_device *psdev)
 212 {
 213         struct pci_dev *pci_dev = NULL;
 214         unsigned long flags;
 215
 216         spin_lock_irqsave(&psdev->lock, flags);
 217         if (!psdev->pdev) {
 218                 psdev->pdev = pdev;
 219                 pci_dev = psdev->dev;
 220         }
 221         spin_unlock_irqrestore(&psdev->lock, flags);
 222
 223         if (pci_dev)
 224                 pcistub_device_get(psdev);
 225
 226         return pci_dev;
 227 }
 228
 229 #ifdef CONFIG_XEN_ACPI
 230 static int pcistub_get_gsi_from_sbdf(unsigned int sbdf)
 231 {
 232         struct pcistub_device *psdev;
 233         int domain = (sbdf >> 16) & 0xffff;
 234         int bus = PCI_BUS_NUM(sbdf);
 235         int slot = PCI_SLOT(sbdf);
 236         int func = PCI_FUNC(sbdf);
 237
 238         psdev = pcistub_device_find(domain, bus, slot, func);
 239
 240         if (!psdev)
 241                 return -ENODEV;
 242
 243         return psdev->gsi;
 244 }
 245 #endif
 246
 247 struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
 248                                             int domain, int bus,
 249                                             int slot, int func)
 250 {
 251         struct pcistub_device *psdev;
 252         struct pci_dev *found_dev = NULL;
 253         unsigned long flags;
 254
 255         spin_lock_irqsave(&pcistub_devices_lock, flags);
 256
 257         psdev = pcistub_device_find_locked(domain, bus, slot, func);
 258         if (psdev)
 259                 found_dev = pcistub_device_get_pci_dev(pdev, psdev);
 260
 261         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 262         return found_dev;
 263 }
 264
 265 struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
 266                                     struct pci_dev *dev)
 267 {
 268         struct pcistub_device *psdev;
 269         struct pci_dev *found_dev = NULL;
 270         unsigned long flags;
 271
 272         spin_lock_irqsave(&pcistub_devices_lock, flags);
 273
 274         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 275                 if (psdev->dev == dev) {
 276                         found_dev = pcistub_device_get_pci_dev(pdev, psdev);
 277                         break;
 278                 }
 279         }
 280
 281         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 282         return found_dev;
 283 }
 284
 285 /*
 286  * Called when:
 287  *  - XenBus state has been reconfigure (pci unplug). See xen_pcibk_remove_device
 288  *  - XenBus state has been disconnected (guest shutdown). See xen_pcibk_xenbus_remove
 289  *  - 'echo BDF > unbind' on pciback module with no guest attached. See pcistub_remove
 290  *  - 'echo BDF > unbind' with a guest still using it. See pcistub_remove
 291  *
 292  *  As such we have to be careful.
 293  *
 294  *  To make this easier, the caller has to hold the device lock.
 295  */
 296 void pcistub_put_pci_dev(struct pci_dev *dev)
 297 {
 298         struct pcistub_device *psdev, *found_psdev = NULL;
 299         unsigned long flags;
 300         struct xen_pcibk_dev_data *dev_data;
 301         int ret;
 302
 303         spin_lock_irqsave(&pcistub_devices_lock, flags);
 304
 305         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 306                 if (psdev->dev == dev) {
 307                         found_psdev = psdev;
 308                         break;
 309                 }
 310         }
 311
 312         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 313         if (WARN_ON(!found_psdev))
 314                 return;
 315
 316         /*hold this lock for avoiding breaking link between
 317         * pcistub and xen_pcibk when AER is in processing
 318         */
 319         down_write(&pcistub_sem);
 320         /* Cleanup our device
 321          * (so it's ready for the next domain)
 322          */
 323         device_lock_assert(&dev->dev);
 324         pcistub_reset_device_state(dev);
 325
 326         dev_data = pci_get_drvdata(dev);
 327         ret = pci_load_saved_state(dev, dev_data->pci_saved_state);
 328         if (!ret) {
 329                 /*
 330                  * The usual sequence is pci_save_state & pci_restore_state
 331                  * but the guest might have messed the configuration space up.
 332                  * Use the initial version (when device was bound to us).
 333                  */
 334                 pci_restore_state(dev);
 335         } else
 336                 dev_info(&dev->dev, "Could not reload PCI state\n");
 337         /* This disables the device. */
 338         xen_pcibk_reset_device(dev);
 339
 340         /* And cleanup up our emulated fields. */
 341         xen_pcibk_config_reset_dev(dev);
 342         xen_pcibk_config_free_dyn_fields(dev);
 343
 344         dev_data->allow_interrupt_control = 0;
 345
 346         xen_unregister_device_domain_owner(dev);
 347
 348         spin_lock_irqsave(&found_psdev->lock, flags);
 349         found_psdev->pdev = NULL;
 350         spin_unlock_irqrestore(&found_psdev->lock, flags);
 351
 352         pcistub_device_put(found_psdev);
 353         up_write(&pcistub_sem);
 354 }
 355
 356 static int pcistub_match_one(struct pci_dev *dev,
 357                              struct pcistub_device_id *pdev_id)
 358 {
 359         /* Match the specified device by domain, bus, slot, func and also if
 360          * any of the device's parent bridges match.
 361          */
 362         for (; dev != NULL; dev = dev->bus->self) {
 363                 if (pci_domain_nr(dev->bus) == pdev_id->domain
 364                     && dev->bus->number == pdev_id->bus
 365                     && dev->devfn == pdev_id->devfn)
 366                         return 1;
 367
 368                 /* Sometimes topmost bridge links to itself. */
 369                 if (dev == dev->bus->self)
 370                         break;
 371         }
 372
 373         return 0;
 374 }
 375
 376 static int pcistub_match(struct pci_dev *dev)
 377 {
 378         struct pcistub_device_id *pdev_id;
 379         unsigned long flags;
 380         int found = 0;
 381
 382         spin_lock_irqsave(&device_ids_lock, flags);
 383         list_for_each_entry(pdev_id, &pcistub_device_ids, slot_list) {
 384                 if (pcistub_match_one(dev, pdev_id)) {
 385                         found = 1;
 386                         break;
 387                 }
 388         }
 389         spin_unlock_irqrestore(&device_ids_lock, flags);
 390
 391         return found;
 392 }
 393
 394 static int pcistub_init_device(struct pcistub_device *psdev)
 395 {
 396         struct xen_pcibk_dev_data *dev_data;
 397         struct pci_dev *dev;
 398 #ifdef CONFIG_XEN_ACPI
 399         int gsi, trigger, polarity;
 400 #endif
 401         int err = 0;
 402
 403         if (!psdev)
 404                 return -EINVAL;
 405
 406         dev = psdev->dev;
 407
 408         dev_dbg(&dev->dev, "initializing...\n");
 409
 410         /* The PCI backend is not intended to be a module (or to work with
 411          * removable PCI devices (yet). If it were, xen_pcibk_config_free()
 412          * would need to be called somewhere to free the memory allocated
 413          * here and then to call kfree(pci_get_drvdata(psdev->dev)).
 414          */
 415         dev_data = kzalloc(sizeof(*dev_data) +  strlen(DRV_NAME "[]")
 416                                 + strlen(pci_name(dev)) + 1, GFP_KERNEL);
 417         if (!dev_data) {
 418                 err = -ENOMEM;
 419                 goto out;
 420         }
 421         pci_set_drvdata(dev, dev_data);
 422
 423         /*
 424          * Setup name for fake IRQ handler. It will only be enabled
 425          * once the device is turned on by the guest.
 426          */
 427         sprintf(dev_data->irq_name, DRV_NAME "[%s]", pci_name(dev));
 428
 429         dev_dbg(&dev->dev, "initializing config\n");
 430
 431         init_waitqueue_head(&xen_pcibk_aer_wait_queue);
 432         err = xen_pcibk_config_init_dev(dev);
 433         if (err)
 434                 goto out;
 435
 436         /* HACK: Force device (& ACPI) to determine what IRQ it's on - we
 437          * must do this here because pcibios_enable_device may specify
 438          * the pci device's true irq (and possibly its other resources)
 439          * if they differ from what's in the configuration space.
 440          * This makes the assumption that the device's resources won't
 441          * change after this point (otherwise this code may break!)
 442          */
 443         dev_dbg(&dev->dev, "enabling device\n");
 444         err = pci_enable_device(dev);
 445         if (err)
 446                 goto config_release;
 447
 448         if (dev->msix_cap) {
 449                 struct physdev_pci_device ppdev = {
 450                         .seg = pci_domain_nr(dev->bus),
 451                         .bus = dev->bus->number,
 452                         .devfn = dev->devfn
 453                 };
 454
 455                 err = HYPERVISOR_physdev_op(PHYSDEVOP_prepare_msix, &ppdev);
 456                 if (err && err != -ENOSYS)
 457                         dev_err(&dev->dev, "MSI-X preparation failed (%d)\n",
 458                                 err);
 459         }
 460
 461         /* We need the device active to save the state. */
 462         dev_dbg(&dev->dev, "save state of device\n");
 463         pci_save_state(dev);
 464         dev_data->pci_saved_state = pci_store_saved_state(dev);
 465         if (!dev_data->pci_saved_state)
 466                 dev_err(&dev->dev, "Could not store PCI conf saved state!\n");
 467         else {
 468                 dev_dbg(&dev->dev, "resetting (FLR, D3, etc) the device\n");
 469                 err = pcistub_reset_device_state(dev);
 470                 if (err)
 471                         goto config_release;
 472                 pci_restore_state(dev);
 473         }
 474
 475 #ifdef CONFIG_XEN_ACPI
 476         if (xen_initial_domain() && xen_pvh_domain()) {
 477                 err = xen_acpi_get_gsi_info(dev, &gsi, &trigger, &polarity);
 478                 if (err) {
 479                         dev_err(&dev->dev, "Fail to get gsi info!\n");
 480                         goto config_release;
 481                 }
 482                 err = xen_pvh_setup_gsi(gsi, trigger, polarity);
 483                 if (err)
 484                         goto config_release;
 485                 psdev->gsi = gsi;
 486         }
 487 #endif
 488
 489         /* Now disable the device (this also ensures some private device
 490          * data is setup before we export)
 491          */
 492         dev_dbg(&dev->dev, "reset device\n");
 493         xen_pcibk_reset_device(dev);
 494
 495         pci_set_dev_assigned(dev);
 496         return 0;
 497
 498 config_release:
 499         xen_pcibk_config_free_dev(dev);
 500
 501 out:
 502         pci_set_drvdata(dev, NULL);
 503         kfree(dev_data);
 504         return err;
 505 }
 506
 507 /*
 508  * Because some initialization still happens on
 509  * devices during fs_initcall, we need to defer
 510  * full initialization of our devices until
 511  * device_initcall.
 512  */
 513 static int __init pcistub_init_devices_late(void)
 514 {
 515         struct pcistub_device *psdev;
 516         unsigned long flags;
 517         int err = 0;
 518
 519         spin_lock_irqsave(&pcistub_devices_lock, flags);
 520
 521         while (!list_empty(&seized_devices)) {
 522                 psdev = container_of(seized_devices.next,
 523                                      struct pcistub_device, dev_list);
 524                 list_del(&psdev->dev_list);
 525
 526                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 527
 528                 err = pcistub_init_device(psdev);
 529                 if (err) {
 530                         dev_err(&psdev->dev->dev,
 531                                 "error %d initializing device\n", err);
 532                         kfree(psdev);
 533                         psdev = NULL;
 534                 }
 535
 536                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 537
 538                 if (psdev)
 539                         list_add_tail(&psdev->dev_list, &pcistub_devices);
 540         }
 541
 542         initialize_devices = 1;
 543
 544         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 545
 546         return 0;
 547 }
 548
 549 static void pcistub_device_id_add_list(struct pcistub_device_id *new,
 550                                        int domain, int bus, unsigned int devfn)
 551 {
 552         struct pcistub_device_id *pci_dev_id;
 553         unsigned long flags;
 554         int found = 0;
 555
 556         spin_lock_irqsave(&device_ids_lock, flags);
 557
 558         list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
 559                 if (pci_dev_id->domain == domain && pci_dev_id->bus == bus &&
 560                     pci_dev_id->devfn == devfn) {
 561                         found = 1;
 562                         break;
 563                 }
 564         }
 565
 566         if (!found) {
 567                 new->domain = domain;
 568                 new->bus = bus;
 569                 new->devfn = devfn;
 570                 list_add_tail(&new->slot_list, &pcistub_device_ids);
 571         }
 572
 573         spin_unlock_irqrestore(&device_ids_lock, flags);
 574
 575         if (found)
 576                 kfree(new);
 577 }
 578
 579 static int pcistub_seize(struct pci_dev *dev,
 580                          struct pcistub_device_id *pci_dev_id)
 581 {
 582         struct pcistub_device *psdev;
 583         unsigned long flags;
 584         int err = 0;
 585
 586         psdev = pcistub_device_alloc(dev);
 587         if (!psdev) {
 588                 kfree(pci_dev_id);
 589                 return -ENOMEM;
 590         }
 591
 592         spin_lock_irqsave(&pcistub_devices_lock, flags);
 593
 594         if (initialize_devices) {
 595                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 596
 597                 /* don't want irqs disabled when calling pcistub_init_device */
 598                 err = pcistub_init_device(psdev);
 599
 600                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 601
 602                 if (!err)
 603                         list_add(&psdev->dev_list, &pcistub_devices);
 604         } else {
 605                 dev_dbg(&dev->dev, "deferring initialization\n");
 606                 list_add(&psdev->dev_list, &seized_devices);
 607         }
 608
 609         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 610
 611         if (err) {
 612                 kfree(pci_dev_id);
 613                 pcistub_device_put(psdev);
 614         } else if (pci_dev_id)
 615                 pcistub_device_id_add_list(pci_dev_id, pci_domain_nr(dev->bus),
 616                                            dev->bus->number, dev->devfn);
 617
 618         return err;
 619 }
 620
 621 /* Called when 'bind'. This means we must _NOT_ call pci_reset_function or
 622  * other functions that take the sysfs lock. */
 623 static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id)
 624 {
 625         int err = 0, match;
 626         struct pcistub_device_id *pci_dev_id = NULL;
 627
 628         dev_dbg(&dev->dev, "probing...\n");
 629
 630         match = pcistub_match(dev);
 631
 632         if ((dev->driver_override &&
 633              !strcmp(dev->driver_override, PCISTUB_DRIVER_NAME)) ||
 634             match) {
 635
 636                 if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL
 637                     && dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
 638                         dev_err(&dev->dev, "can't export pci devices that "
 639                                 "don't have a normal (0) or bridge (1) "
 640                                 "header type!\n");
 641                         err = -ENODEV;
 642                         goto out;
 643                 }
 644
 645                 if (!match) {
 646                         pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
 647                         if (!pci_dev_id) {
 648                                 err = -ENOMEM;
 649                                 goto out;
 650                         }
 651                 }
 652
 653                 dev_info(&dev->dev, "seizing device\n");
 654                 err = pcistub_seize(dev, pci_dev_id);
 655         } else
 656                 /* Didn't find the device */
 657                 err = -ENODEV;
 658
 659 out:
 660         return err;
 661 }
 662
 663 /* Called when 'unbind'. This means we must _NOT_ call pci_reset_function or
 664  * other functions that take the sysfs lock. */
 665 static void pcistub_remove(struct pci_dev *dev)
 666 {
 667         struct pcistub_device *psdev, *found_psdev = NULL;
 668         unsigned long flags;
 669
 670         dev_dbg(&dev->dev, "removing\n");
 671
 672         spin_lock_irqsave(&pcistub_devices_lock, flags);
 673
 674         xen_pcibk_config_quirk_release(dev);
 675
 676         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
 677                 if (psdev->dev == dev) {
 678                         found_psdev = psdev;
 679                         break;
 680                 }
 681         }
 682
 683         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 684
 685         if (found_psdev) {
 686                 dev_dbg(&dev->dev, "found device to remove %s\n",
 687                         found_psdev->pdev ? "- in-use" : "");
 688
 689                 if (found_psdev->pdev) {
 690                         int domid = xen_find_device_domain_owner(dev);
 691
 692                         dev_warn(&dev->dev, "****** removing device %s while still in-use by domain %d! ******\n",
 693                                pci_name(found_psdev->dev), domid);
 694                         dev_warn(&dev->dev, "****** driver domain may still access this device's i/o resources!\n");
 695                         dev_warn(&dev->dev, "****** shutdown driver domain before binding device\n");
 696                         dev_warn(&dev->dev, "****** to other drivers or domains\n");
 697
 698                         /* N.B. This ends up calling pcistub_put_pci_dev which ends up
 699                          * doing the FLR. */
 700                         xen_pcibk_release_pci_dev(found_psdev->pdev,
 701                                                 found_psdev->dev,
 702                                                 false /* caller holds the lock. */);
 703                 }
 704
 705                 spin_lock_irqsave(&pcistub_devices_lock, flags);
 706                 list_del(&found_psdev->dev_list);
 707                 spin_unlock_irqrestore(&pcistub_devices_lock, flags);
 708
 709                 /* the final put for releasing from the list */
 710                 pcistub_device_put(found_psdev);
 711         }
 712 }
 713
 714 static const struct pci_device_id pcistub_ids[] = {
 715         {
 716          .vendor = PCI_ANY_ID,
 717          .device = PCI_ANY_ID,
 718          .subvendor = PCI_ANY_ID,
 719          .subdevice = PCI_ANY_ID,
 720          },
 721         {0,},
 722 };
 723
 724 #define PCI_NODENAME_MAX 40
 725 static void kill_domain_by_device(struct pcistub_device *psdev)
 726 {
 727         struct xenbus_transaction xbt;
 728         int err;
 729         char nodename[PCI_NODENAME_MAX];
 730
 731         BUG_ON(!psdev);
 732         snprintf(nodename, PCI_NODENAME_MAX, "/local/domain/0/backend/pci/%d/0",
 733                 psdev->pdev->xdev->otherend_id);
 734
 735 again:
 736         err = xenbus_transaction_start(&xbt);
 737         if (err) {
 738                 dev_err(&psdev->dev->dev,
 739                         "error %d when start xenbus transaction\n", err);
 740                 return;
 741         }
 742         /*PV AER handlers will set this flag*/
 743         xenbus_printf(xbt, nodename, "aerState" , "aerfail");
 744         err = xenbus_transaction_end(xbt, 0);
 745         if (err) {
 746                 if (err == -EAGAIN)
 747                         goto again;
 748                 dev_err(&psdev->dev->dev,
 749                         "error %d when end xenbus transaction\n", err);
 750                 return;
 751         }
 752 }
 753
 754 /* For each aer recovery step error_detected, mmio_enabled, etc, front_end and
 755  * backend need to have cooperation. In xen_pcibk, those steps will do similar
 756  * jobs: send service request and waiting for front_end response.
 757 */
 758 static pci_ers_result_t common_process(struct pcistub_device *psdev,
 759                                        pci_channel_state_t state, int aer_cmd,
 760                                        pci_ers_result_t result)
 761 {
 762         pci_ers_result_t res = result;
 763         struct xen_pcie_aer_op *aer_op;
 764         struct xen_pcibk_device *pdev = psdev->pdev;
 765         struct xen_pci_sharedinfo *sh_info = pdev->sh_info;
 766         int ret;
 767
 768         /*with PV AER drivers*/
 769         aer_op = &(sh_info->aer_op);
 770         aer_op->cmd = aer_cmd ;
 771         /*useful for error_detected callback*/
 772         aer_op->err = state;
 773         /*pcifront_end BDF*/
 774         ret = xen_pcibk_get_pcifront_dev(psdev->dev, psdev->pdev,
 775                 &aer_op->domain, &aer_op->bus, &aer_op->devfn);
 776         if (!ret) {
 777                 dev_err(&psdev->dev->dev, "failed to get pcifront device\n");
 778                 return PCI_ERS_RESULT_NONE;
 779         }
 780         wmb();
 781
 782         dev_dbg(&psdev->dev->dev, "aer_op %x dom %x bus %x devfn %x\n",
 783                         aer_cmd, aer_op->domain, aer_op->bus, aer_op->devfn);
 784         /*local flag to mark there's aer request, xen_pcibk callback will use
 785         * this flag to judge whether we need to check pci-front give aer
 786         * service ack signal
 787         */
 788         set_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags);
 789
 790         /*It is possible that a pcifront conf_read_write ops request invokes
 791         * the callback which cause the spurious execution of wake_up.
 792         * Yet it is harmless and better than a spinlock here
 793         */
 794         set_bit(_XEN_PCIB_active,
 795                 (unsigned long *)&sh_info->flags);
 796         wmb();
 797         notify_remote_via_irq(pdev->evtchn_irq);
 798
 799         /* Enable IRQ to signal "request done". */
 800         xen_pcibk_lateeoi(pdev, 0);
 801
 802         ret = wait_event_timeout(xen_pcibk_aer_wait_queue,
 803                                  !(test_bit(_XEN_PCIB_active, (unsigned long *)
 804                                  &sh_info->flags)), 300*HZ);
 805
 806         /* Enable IRQ for pcifront request if not already active. */
 807         if (!test_bit(_PDEVF_op_active, &pdev->flags))
 808                 xen_pcibk_lateeoi(pdev, 0);
 809
 810         if (!ret) {
 811                 if (test_bit(_XEN_PCIB_active,
 812                         (unsigned long *)&sh_info->flags)) {
 813                         dev_err(&psdev->dev->dev,
 814                                 "pcifront aer process not responding!\n");
 815                         clear_bit(_XEN_PCIB_active,
 816                           (unsigned long *)&sh_info->flags);
 817                         aer_op->err = PCI_ERS_RESULT_NONE;
 818                         return res;
 819                 }
 820         }
 821         clear_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags);
 822
 823         res = (__force pci_ers_result_t)aer_op->err;
 824         return res;
 825 }
 826
 827 /*
 828 * xen_pcibk_slot_reset: it will send the slot_reset request to  pcifront in case
 829 * of the device driver could provide this service, and then wait for pcifront
 830 * ack.
 831 * @dev: pointer to PCI devices
 832 * return value is used by aer_core do_recovery policy
 833 */
 834 static pci_ers_result_t xen_pcibk_slot_reset(struct pci_dev *dev)
 835 {
 836         struct pcistub_device *psdev;
 837         pci_ers_result_t result;
 838
 839         result = PCI_ERS_RESULT_RECOVERED;
 840         dev_dbg(&dev->dev, "xen_pcibk_slot_reset(bus:%x,devfn:%x)\n",
 841                 dev->bus->number, dev->devfn);
 842
 843         down_write(&pcistub_sem);
 844         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 845                                 dev->bus->number,
 846                                 PCI_SLOT(dev->devfn),
 847                                 PCI_FUNC(dev->devfn));
 848
 849         if (!psdev || !psdev->pdev) {
 850                 dev_err(&dev->dev, "device is not found/assigned\n");
 851                 goto end;
 852         }
 853
 854         if (!psdev->pdev->sh_info) {
 855                 dev_err(&dev->dev, "device is not connected or owned"
 856                         " by HVM, kill it\n");
 857                 kill_domain_by_device(psdev);
 858                 goto end;
 859         }
 860
 861         if (!test_bit(_XEN_PCIB_AERHANDLER,
 862                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 863                 dev_err(&dev->dev,
 864                         "guest with no AER driver should have been killed\n");
 865                 goto end;
 866         }
 867         result = common_process(psdev, pci_channel_io_normal, XEN_PCI_OP_aer_slotreset, result);
 868
 869         if (result == PCI_ERS_RESULT_NONE ||
 870                 result == PCI_ERS_RESULT_DISCONNECT) {
 871                 dev_dbg(&dev->dev,
 872                         "No AER slot_reset service or disconnected!\n");
 873                 kill_domain_by_device(psdev);
 874         }
 875 end:
 876         if (psdev)
 877                 pcistub_device_put(psdev);
 878         up_write(&pcistub_sem);
 879         return result;
 880
 881 }
 882
 883
 884 /*xen_pcibk_mmio_enabled: it will send the mmio_enabled request to  pcifront
 885 * in case of the device driver could provide this service, and then wait
 886 * for pcifront ack
 887 * @dev: pointer to PCI devices
 888 * return value is used by aer_core do_recovery policy
 889 */
 890
 891 static pci_ers_result_t xen_pcibk_mmio_enabled(struct pci_dev *dev)
 892 {
 893         struct pcistub_device *psdev;
 894         pci_ers_result_t result;
 895
 896         result = PCI_ERS_RESULT_RECOVERED;
 897         dev_dbg(&dev->dev, "xen_pcibk_mmio_enabled(bus:%x,devfn:%x)\n",
 898                 dev->bus->number, dev->devfn);
 899
 900         down_write(&pcistub_sem);
 901         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 902                                 dev->bus->number,
 903                                 PCI_SLOT(dev->devfn),
 904                                 PCI_FUNC(dev->devfn));
 905
 906         if (!psdev || !psdev->pdev) {
 907                 dev_err(&dev->dev, "device is not found/assigned\n");
 908                 goto end;
 909         }
 910
 911         if (!psdev->pdev->sh_info) {
 912                 dev_err(&dev->dev, "device is not connected or owned"
 913                         " by HVM, kill it\n");
 914                 kill_domain_by_device(psdev);
 915                 goto end;
 916         }
 917
 918         if (!test_bit(_XEN_PCIB_AERHANDLER,
 919                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 920                 dev_err(&dev->dev,
 921                         "guest with no AER driver should have been killed\n");
 922                 goto end;
 923         }
 924         result = common_process(psdev, pci_channel_io_normal, XEN_PCI_OP_aer_mmio, result);
 925
 926         if (result == PCI_ERS_RESULT_NONE ||
 927                 result == PCI_ERS_RESULT_DISCONNECT) {
 928                 dev_dbg(&dev->dev,
 929                         "No AER mmio_enabled service or disconnected!\n");
 930                 kill_domain_by_device(psdev);
 931         }
 932 end:
 933         if (psdev)
 934                 pcistub_device_put(psdev);
 935         up_write(&pcistub_sem);
 936         return result;
 937 }
 938
 939 /*xen_pcibk_error_detected: it will send the error_detected request to  pcifront
 940 * in case of the device driver could provide this service, and then wait
 941 * for pcifront ack.
 942 * @dev: pointer to PCI devices
 943 * @error: the current PCI connection state
 944 * return value is used by aer_core do_recovery policy
 945 */
 946
 947 static pci_ers_result_t xen_pcibk_error_detected(struct pci_dev *dev,
 948         pci_channel_state_t error)
 949 {
 950         struct pcistub_device *psdev;
 951         pci_ers_result_t result;
 952
 953         result = PCI_ERS_RESULT_CAN_RECOVER;
 954         dev_dbg(&dev->dev, "xen_pcibk_error_detected(bus:%x,devfn:%x)\n",
 955                 dev->bus->number, dev->devfn);
 956
 957         down_write(&pcistub_sem);
 958         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
 959                                 dev->bus->number,
 960                                 PCI_SLOT(dev->devfn),
 961                                 PCI_FUNC(dev->devfn));
 962
 963         if (!psdev || !psdev->pdev) {
 964                 dev_err(&dev->dev, "device is not found/assigned\n");
 965                 goto end;
 966         }
 967
 968         if (!psdev->pdev->sh_info) {
 969                 dev_err(&dev->dev, "device is not connected or owned"
 970                         " by HVM, kill it\n");
 971                 kill_domain_by_device(psdev);
 972                 goto end;
 973         }
 974
 975         /*Guest owns the device yet no aer handler regiested, kill guest*/
 976         if (!test_bit(_XEN_PCIB_AERHANDLER,
 977                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
 978                 dev_dbg(&dev->dev, "guest may have no aer driver, kill it\n");
 979                 kill_domain_by_device(psdev);
 980                 goto end;
 981         }
 982         result = common_process(psdev, error, XEN_PCI_OP_aer_detected, result);
 983
 984         if (result == PCI_ERS_RESULT_NONE ||
 985                 result == PCI_ERS_RESULT_DISCONNECT) {
 986                 dev_dbg(&dev->dev,
 987                         "No AER error_detected service or disconnected!\n");
 988                 kill_domain_by_device(psdev);
 989         }
 990 end:
 991         if (psdev)
 992                 pcistub_device_put(psdev);
 993         up_write(&pcistub_sem);
 994         return result;
 995 }
 996
 997 /*xen_pcibk_error_resume: it will send the error_resume request to  pcifront
 998 * in case of the device driver could provide this service, and then wait
 999 * for pcifront ack.
1000 * @dev: pointer to PCI devices
1001 */
1002
1003 static void xen_pcibk_error_resume(struct pci_dev *dev)
1004 {
1005         struct pcistub_device *psdev;
1006
1007         dev_dbg(&dev->dev, "xen_pcibk_error_resume(bus:%x,devfn:%x)\n",
1008                 dev->bus->number, dev->devfn);
1009
1010         down_write(&pcistub_sem);
1011         psdev = pcistub_device_find(pci_domain_nr(dev->bus),
1012                                 dev->bus->number,
1013                                 PCI_SLOT(dev->devfn),
1014                                 PCI_FUNC(dev->devfn));
1015
1016         if (!psdev || !psdev->pdev) {
1017                 dev_err(&dev->dev, "device is not found/assigned\n");
1018                 goto end;
1019         }
1020
1021         if (!psdev->pdev->sh_info) {
1022                 dev_err(&dev->dev, "device is not connected or owned"
1023                         " by HVM, kill it\n");
1024                 kill_domain_by_device(psdev);
1025                 goto end;
1026         }
1027
1028         if (!test_bit(_XEN_PCIB_AERHANDLER,
1029                 (unsigned long *)&psdev->pdev->sh_info->flags)) {
1030                 dev_err(&dev->dev,
1031                         "guest with no AER driver should have been killed\n");
1032                 kill_domain_by_device(psdev);
1033                 goto end;
1034         }
1035         common_process(psdev, pci_channel_io_normal, XEN_PCI_OP_aer_resume,
1036                        PCI_ERS_RESULT_RECOVERED);
1037 end:
1038         if (psdev)
1039                 pcistub_device_put(psdev);
1040         up_write(&pcistub_sem);
1041         return;
1042 }
1043
1044 /*add xen_pcibk AER handling*/
1045 static const struct pci_error_handlers xen_pcibk_error_handler = {
1046         .error_detected = xen_pcibk_error_detected,
1047         .mmio_enabled = xen_pcibk_mmio_enabled,
1048         .slot_reset = xen_pcibk_slot_reset,
1049         .resume = xen_pcibk_error_resume,
1050 };
1051
1052 /*
1053  * Note: There is no MODULE_DEVICE_TABLE entry here because this isn't
1054  * for a normal device. I don't want it to be loaded automatically.
1055  */
1056
1057 static struct pci_driver xen_pcibk_pci_driver = {
1058         /* The name should be xen_pciback, but until the tools are updated
1059          * we will keep it as pciback. */
1060         .name = PCISTUB_DRIVER_NAME,
1061         .id_table = pcistub_ids,
1062         .probe = pcistub_probe,
1063         .remove = pcistub_remove,
1064         .err_handler = &xen_pcibk_error_handler,
1065 };
1066
1067 static inline int str_to_slot(const char *buf, int *domain, int *bus,
1068                               int *slot, int *func)
1069 {
1070         int parsed = 0;
1071
1072         switch (sscanf(buf, " %x:%x:%x.%x %n", domain, bus, slot, func,
1073                        &parsed)) {
1074         case 3:
1075                 *func = -1;
1076                 sscanf(buf, " %x:%x:%x.* %n", domain, bus, slot, &parsed);
1077                 break;
1078         case 2:
1079                 *slot = *func = -1;
1080                 sscanf(buf, " %x:%x:*.* %n", domain, bus, &parsed);
1081                 break;
1082         }
1083         if (parsed && !buf[parsed])
1084                 return 0;
1085
1086         /* try again without domain */
1087         *domain = 0;
1088         switch (sscanf(buf, " %x:%x.%x %n", bus, slot, func, &parsed)) {
1089         case 2:
1090                 *func = -1;
1091                 sscanf(buf, " %x:%x.* %n", bus, slot, &parsed);
1092                 break;
1093         case 1:
1094                 *slot = *func = -1;
1095                 sscanf(buf, " %x:*.* %n", bus, &parsed);
1096                 break;
1097         }
1098         if (parsed && !buf[parsed])
1099                 return 0;
1100
1101         return -EINVAL;
1102 }
1103
1104 static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
1105                                *slot, int *func, int *reg, int *size, int *mask)
1106 {
1107         int parsed = 0;
1108
1109         sscanf(buf, " %x:%x:%x.%x-%x:%x:%x %n", domain, bus, slot, func,
1110                reg, size, mask, &parsed);
1111         if (parsed && !buf[parsed])
1112                 return 0;
1113
1114         /* try again without domain */
1115         *domain = 0;
1116         sscanf(buf, " %x:%x.%x-%x:%x:%x %n", bus, slot, func, reg, size,
1117                mask, &parsed);
1118         if (parsed && !buf[parsed])
1119                 return 0;
1120
1121         return -EINVAL;
1122 }
1123
1124 static int pcistub_device_id_add(int domain, int bus, int slot, int func)
1125 {
1126         struct pcistub_device_id *pci_dev_id;
1127         int rc = 0, devfn = PCI_DEVFN(slot, func);
1128
1129         if (slot < 0) {
1130                 for (slot = 0; !rc && slot < 32; ++slot)
1131                         rc = pcistub_device_id_add(domain, bus, slot, func);
1132                 return rc;
1133         }
1134
1135         if (func < 0) {
1136                 for (func = 0; !rc && func < 8; ++func)
1137                         rc = pcistub_device_id_add(domain, bus, slot, func);
1138                 return rc;
1139         }
1140
1141         if ((
1142 #if !defined(MODULE) /* pci_domains_supported is not being exported */ \
1143     || !defined(CONFIG_PCI_DOMAINS)
1144              !pci_domains_supported ? domain :
1145 #endif
1146              domain < 0 || domain > 0xffff)
1147             || bus < 0 || bus > 0xff
1148             || PCI_SLOT(devfn) != slot
1149             || PCI_FUNC(devfn) != func)
1150                 return -EINVAL;
1151
1152         pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
1153         if (!pci_dev_id)
1154                 return -ENOMEM;
1155
1156         pr_debug("wants to seize %04x:%02x:%02x.%d\n",
1157                  domain, bus, slot, func);
1158
1159         pcistub_device_id_add_list(pci_dev_id, domain, bus, devfn);
1160
1161         return 0;
1162 }
1163
1164 static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
1165 {
1166         struct pcistub_device_id *pci_dev_id, *t;
1167         int err = -ENOENT;
1168         unsigned long flags;
1169
1170         spin_lock_irqsave(&device_ids_lock, flags);
1171         list_for_each_entry_safe(pci_dev_id, t, &pcistub_device_ids,
1172                                  slot_list) {
1173                 if (pci_dev_id->domain == domain && pci_dev_id->bus == bus
1174                     && (slot < 0 || PCI_SLOT(pci_dev_id->devfn) == slot)
1175                     && (func < 0 || PCI_FUNC(pci_dev_id->devfn) == func)) {
1176                         /* Don't break; here because it's possible the same
1177                          * slot could be in the list more than once
1178                          */
1179                         list_del(&pci_dev_id->slot_list);
1180                         kfree(pci_dev_id);
1181
1182                         err = 0;
1183
1184                         pr_debug("removed %04x:%02x:%02x.%d from seize list\n",
1185                                  domain, bus, slot, func);
1186                 }
1187         }
1188         spin_unlock_irqrestore(&device_ids_lock, flags);
1189
1190         return err;
1191 }
1192
1193 static int pcistub_reg_add(int domain, int bus, int slot, int func,
1194                            unsigned int reg, unsigned int size,
1195                            unsigned int mask)
1196 {
1197         int err = 0;
1198         struct pcistub_device *psdev;
1199         struct pci_dev *dev;
1200         struct config_field *field;
1201
1202         if (reg > 0xfff || (size < 4 && (mask >> (size * 8))))
1203                 return -EINVAL;
1204
1205         psdev = pcistub_device_find(domain, bus, slot, func);
1206         if (!psdev) {
1207                 err = -ENODEV;
1208                 goto out;
1209         }
1210         dev = psdev->dev;
1211
1212         field = kzalloc(sizeof(*field), GFP_KERNEL);
1213         if (!field) {
1214                 err = -ENOMEM;
1215                 goto out;
1216         }
1217
1218         field->offset = reg;
1219         field->size = size;
1220         field->mask = mask;
1221         field->init = NULL;
1222         field->reset = NULL;
1223         field->release = NULL;
1224         field->clean = xen_pcibk_config_field_free;
1225
1226         err = xen_pcibk_config_quirks_add_field(dev, field);
1227         if (err)
1228                 kfree(field);
1229 out:
1230         if (psdev)
1231                 pcistub_device_put(psdev);
1232         return err;
1233 }
1234
1235 static ssize_t new_slot_store(struct device_driver *drv, const char *buf,
1236                               size_t count)
1237 {
1238         int domain, bus, slot, func;
1239         int err;
1240
1241         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1242         if (err)
1243                 goto out;
1244
1245         err = pcistub_device_id_add(domain, bus, slot, func);
1246
1247 out:
1248         if (!err)
1249                 err = count;
1250         return err;
1251 }
1252 static DRIVER_ATTR_WO(new_slot);
1253
1254 static ssize_t remove_slot_store(struct device_driver *drv, const char *buf,
1255                                  size_t count)
1256 {
1257         int domain, bus, slot, func;
1258         int err;
1259
1260         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1261         if (err)
1262                 goto out;
1263
1264         err = pcistub_device_id_remove(domain, bus, slot, func);
1265
1266 out:
1267         if (!err)
1268                 err = count;
1269         return err;
1270 }
1271 static DRIVER_ATTR_WO(remove_slot);
1272
1273 static ssize_t slots_show(struct device_driver *drv, char *buf)
1274 {
1275         struct pcistub_device_id *pci_dev_id;
1276         size_t count = 0;
1277         unsigned long flags;
1278
1279         spin_lock_irqsave(&device_ids_lock, flags);
1280         list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) {
1281                 if (count >= PAGE_SIZE)
1282                         break;
1283
1284                 count += scnprintf(buf + count, PAGE_SIZE - count,
1285                                    "%04x:%02x:%02x.%d\n",
1286                                    pci_dev_id->domain, pci_dev_id->bus,
1287                                    PCI_SLOT(pci_dev_id->devfn),
1288                                    PCI_FUNC(pci_dev_id->devfn));
1289         }
1290         spin_unlock_irqrestore(&device_ids_lock, flags);
1291
1292         return count;
1293 }
1294 static DRIVER_ATTR_RO(slots);
1295
1296 static ssize_t irq_handlers_show(struct device_driver *drv, char *buf)
1297 {
1298         struct pcistub_device *psdev;
1299         struct xen_pcibk_dev_data *dev_data;
1300         size_t count = 0;
1301         unsigned long flags;
1302
1303         spin_lock_irqsave(&pcistub_devices_lock, flags);
1304         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1305                 if (count >= PAGE_SIZE)
1306                         break;
1307                 if (!psdev->dev)
1308                         continue;
1309                 dev_data = pci_get_drvdata(psdev->dev);
1310                 if (!dev_data)
1311                         continue;
1312                 count +=
1313                     scnprintf(buf + count, PAGE_SIZE - count,
1314                               "%s:%s:%sing:%ld\n",
1315                               pci_name(psdev->dev),
1316                               dev_data->isr_on ? "on" : "off",
1317                               dev_data->ack_intr ? "ack" : "not ack",
1318                               dev_data->handled);
1319         }
1320         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1321         return count;
1322 }
1323 static DRIVER_ATTR_RO(irq_handlers);
1324
1325 static ssize_t irq_handler_state_store(struct device_driver *drv,
1326                                        const char *buf, size_t count)
1327 {
1328         struct pcistub_device *psdev;
1329         struct xen_pcibk_dev_data *dev_data;
1330         int domain, bus, slot, func;
1331         int err;
1332
1333         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1334         if (err)
1335                 return err;
1336
1337         psdev = pcistub_device_find(domain, bus, slot, func);
1338         if (!psdev) {
1339                 err = -ENOENT;
1340                 goto out;
1341         }
1342
1343         dev_data = pci_get_drvdata(psdev->dev);
1344         if (!dev_data) {
1345                 err = -ENOENT;
1346                 goto out;
1347         }
1348
1349         dev_dbg(&psdev->dev->dev, "%s fake irq handler: %d->%d\n",
1350                 dev_data->irq_name, dev_data->isr_on,
1351                 !dev_data->isr_on);
1352
1353         dev_data->isr_on = !(dev_data->isr_on);
1354         if (dev_data->isr_on)
1355                 dev_data->ack_intr = 1;
1356 out:
1357         if (psdev)
1358                 pcistub_device_put(psdev);
1359         if (!err)
1360                 err = count;
1361         return err;
1362 }
1363 static DRIVER_ATTR_WO(irq_handler_state);
1364
1365 static ssize_t quirks_store(struct device_driver *drv, const char *buf,
1366                             size_t count)
1367 {
1368         int domain, bus, slot, func, reg, size, mask;
1369         int err;
1370
1371         err = str_to_quirk(buf, &domain, &bus, &slot, &func, &reg, &size,
1372                            &mask);
1373         if (err)
1374                 goto out;
1375
1376         err = pcistub_reg_add(domain, bus, slot, func, reg, size, mask);
1377
1378 out:
1379         if (!err)
1380                 err = count;
1381         return err;
1382 }
1383
1384 static ssize_t quirks_show(struct device_driver *drv, char *buf)
1385 {
1386         int count = 0;
1387         unsigned long flags;
1388         struct xen_pcibk_config_quirk *quirk;
1389         struct xen_pcibk_dev_data *dev_data;
1390         const struct config_field *field;
1391         const struct config_field_entry *cfg_entry;
1392
1393         spin_lock_irqsave(&device_ids_lock, flags);
1394         list_for_each_entry(quirk, &xen_pcibk_quirks, quirks_list) {
1395                 if (count >= PAGE_SIZE)
1396                         goto out;
1397
1398                 count += scnprintf(buf + count, PAGE_SIZE - count,
1399                                    "%02x:%02x.%01x\n\t%04x:%04x:%04x:%04x\n",
1400                                    quirk->pdev->bus->number,
1401                                    PCI_SLOT(quirk->pdev->devfn),
1402                                    PCI_FUNC(quirk->pdev->devfn),
1403                                    quirk->devid.vendor, quirk->devid.device,
1404                                    quirk->devid.subvendor,
1405                                    quirk->devid.subdevice);
1406
1407                 dev_data = pci_get_drvdata(quirk->pdev);
1408
1409                 list_for_each_entry(cfg_entry, &dev_data->config_fields, list) {
1410                         field = cfg_entry->field;
1411                         if (count >= PAGE_SIZE)
1412                                 goto out;
1413
1414                         count += scnprintf(buf + count, PAGE_SIZE - count,
1415                                            "\t\t%08x:%01x:%08x\n",
1416                                            cfg_entry->base_offset +
1417                                            field->offset, field->size,
1418                                            field->mask);
1419                 }
1420         }
1421
1422 out:
1423         spin_unlock_irqrestore(&device_ids_lock, flags);
1424
1425         return count;
1426 }
1427 static DRIVER_ATTR_RW(quirks);
1428
1429 static ssize_t permissive_store(struct device_driver *drv, const char *buf,
1430                                 size_t count)
1431 {
1432         int domain, bus, slot, func;
1433         int err;
1434         struct pcistub_device *psdev;
1435         struct xen_pcibk_dev_data *dev_data;
1436
1437         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1438         if (err)
1439                 goto out;
1440
1441         psdev = pcistub_device_find(domain, bus, slot, func);
1442         if (!psdev) {
1443                 err = -ENODEV;
1444                 goto out;
1445         }
1446
1447         dev_data = pci_get_drvdata(psdev->dev);
1448         /* the driver data for a device should never be null at this point */
1449         if (!dev_data) {
1450                 err = -ENXIO;
1451                 goto release;
1452         }
1453         if (!dev_data->permissive) {
1454                 dev_data->permissive = 1;
1455                 /* Let user know that what they're doing could be unsafe */
1456                 dev_warn(&psdev->dev->dev, "enabling permissive mode "
1457                          "configuration space accesses!\n");
1458                 dev_warn(&psdev->dev->dev,
1459                          "permissive mode is potentially unsafe!\n");
1460         }
1461 release:
1462         pcistub_device_put(psdev);
1463 out:
1464         if (!err)
1465                 err = count;
1466         return err;
1467 }
1468
1469 static ssize_t permissive_show(struct device_driver *drv, char *buf)
1470 {
1471         struct pcistub_device *psdev;
1472         struct xen_pcibk_dev_data *dev_data;
1473         size_t count = 0;
1474         unsigned long flags;
1475         spin_lock_irqsave(&pcistub_devices_lock, flags);
1476         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1477                 if (count >= PAGE_SIZE)
1478                         break;
1479                 if (!psdev->dev)
1480                         continue;
1481                 dev_data = pci_get_drvdata(psdev->dev);
1482                 if (!dev_data || !dev_data->permissive)
1483                         continue;
1484                 count +=
1485                     scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
1486                               pci_name(psdev->dev));
1487         }
1488         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1489         return count;
1490 }
1491 static DRIVER_ATTR_RW(permissive);
1492
1493 static ssize_t allow_interrupt_control_store(struct device_driver *drv,
1494                                              const char *buf, size_t count)
1495 {
1496         int domain, bus, slot, func;
1497         int err;
1498         struct pcistub_device *psdev;
1499         struct xen_pcibk_dev_data *dev_data;
1500
1501         err = str_to_slot(buf, &domain, &bus, &slot, &func);
1502         if (err)
1503                 goto out;
1504
1505         psdev = pcistub_device_find(domain, bus, slot, func);
1506         if (!psdev) {
1507                 err = -ENODEV;
1508                 goto out;
1509         }
1510
1511         dev_data = pci_get_drvdata(psdev->dev);
1512         /* the driver data for a device should never be null at this point */
1513         if (!dev_data) {
1514                 err = -ENXIO;
1515                 goto release;
1516         }
1517         dev_data->allow_interrupt_control = 1;
1518 release:
1519         pcistub_device_put(psdev);
1520 out:
1521         if (!err)
1522                 err = count;
1523         return err;
1524 }
1525
1526 static ssize_t allow_interrupt_control_show(struct device_driver *drv,
1527                                             char *buf)
1528 {
1529         struct pcistub_device *psdev;
1530         struct xen_pcibk_dev_data *dev_data;
1531         size_t count = 0;
1532         unsigned long flags;
1533
1534         spin_lock_irqsave(&pcistub_devices_lock, flags);
1535         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1536                 if (count >= PAGE_SIZE)
1537                         break;
1538                 if (!psdev->dev)
1539                         continue;
1540                 dev_data = pci_get_drvdata(psdev->dev);
1541                 if (!dev_data || !dev_data->allow_interrupt_control)
1542                         continue;
1543                 count +=
1544                     scnprintf(buf + count, PAGE_SIZE - count, "%s\n",
1545                               pci_name(psdev->dev));
1546         }
1547         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1548         return count;
1549 }
1550 static DRIVER_ATTR_RW(allow_interrupt_control);
1551
1552 static void pcistub_exit(void)
1553 {
1554         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_new_slot);
1555         driver_remove_file(&xen_pcibk_pci_driver.driver,
1556                            &driver_attr_remove_slot);
1557         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_slots);
1558         driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_quirks);
1559         driver_remove_file(&xen_pcibk_pci_driver.driver,
1560                            &driver_attr_permissive);
1561         driver_remove_file(&xen_pcibk_pci_driver.driver,
1562                            &driver_attr_allow_interrupt_control);
1563         driver_remove_file(&xen_pcibk_pci_driver.driver,
1564                            &driver_attr_irq_handlers);
1565         driver_remove_file(&xen_pcibk_pci_driver.driver,
1566                            &driver_attr_irq_handler_state);
1567         pci_unregister_driver(&xen_pcibk_pci_driver);
1568 }
1569
1570 static int __init pcistub_init(void)
1571 {
1572         int pos = 0;
1573         int err = 0;
1574         int domain, bus, slot, func;
1575         int parsed;
1576
1577         if (pci_devs_to_hide && *pci_devs_to_hide) {
1578                 do {
1579                         parsed = 0;
1580
1581                         err = sscanf(pci_devs_to_hide + pos,
1582                                      " (%x:%x:%x.%x) %n",
1583                                      &domain, &bus, &slot, &func, &parsed);
1584                         switch (err) {
1585                         case 3:
1586                                 func = -1;
1587                                 sscanf(pci_devs_to_hide + pos,
1588                                        " (%x:%x:%x.*) %n",
1589                                        &domain, &bus, &slot, &parsed);
1590                                 break;
1591                         case 2:
1592                                 slot = func = -1;
1593                                 sscanf(pci_devs_to_hide + pos,
1594                                        " (%x:%x:*.*) %n",
1595                                        &domain, &bus, &parsed);
1596                                 break;
1597                         }
1598
1599                         if (!parsed) {
1600                                 domain = 0;
1601                                 err = sscanf(pci_devs_to_hide + pos,
1602                                              " (%x:%x.%x) %n",
1603                                              &bus, &slot, &func, &parsed);
1604                                 switch (err) {
1605                                 case 2:
1606                                         func = -1;
1607                                         sscanf(pci_devs_to_hide + pos,
1608                                                " (%x:%x.*) %n",
1609                                                &bus, &slot, &parsed);
1610                                         break;
1611                                 case 1:
1612                                         slot = func = -1;
1613                                         sscanf(pci_devs_to_hide + pos,
1614                                                " (%x:*.*) %n",
1615                                                &bus, &parsed);
1616                                         break;
1617                                 }
1618                         }
1619
1620                         if (parsed <= 0)
1621                                 goto parse_error;
1622
1623                         err = pcistub_device_id_add(domain, bus, slot, func);
1624                         if (err)
1625                                 goto out;
1626
1627                         pos += parsed;
1628                 } while (pci_devs_to_hide[pos]);
1629         }
1630
1631         /* If we're the first PCI Device Driver to register, we're the
1632          * first one to get offered PCI devices as they become
1633          * available (and thus we can be the first to grab them)
1634          */
1635         err = pci_register_driver(&xen_pcibk_pci_driver);
1636         if (err < 0)
1637                 goto out;
1638
1639         err = driver_create_file(&xen_pcibk_pci_driver.driver,
1640                                  &driver_attr_new_slot);
1641         if (!err)
1642                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1643                                          &driver_attr_remove_slot);
1644         if (!err)
1645                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1646                                          &driver_attr_slots);
1647         if (!err)
1648                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1649                                          &driver_attr_quirks);
1650         if (!err)
1651                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1652                                          &driver_attr_permissive);
1653         if (!err)
1654                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1655                                          &driver_attr_allow_interrupt_control);
1656
1657         if (!err)
1658                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1659                                          &driver_attr_irq_handlers);
1660         if (!err)
1661                 err = driver_create_file(&xen_pcibk_pci_driver.driver,
1662                                         &driver_attr_irq_handler_state);
1663         if (err)
1664                 pcistub_exit();
1665
1666 out:
1667         return err;
1668
1669 parse_error:
1670         pr_err("Error parsing pci_devs_to_hide at \"%s\"\n",
1671                pci_devs_to_hide + pos);
1672         return -EINVAL;
1673 }
1674
1675 #ifndef MODULE
1676 /*
1677  * fs_initcall happens before device_initcall
1678  * so xen_pcibk *should* get called first (b/c we
1679  * want to suck up any device before other drivers
1680  * get a chance by being the first pci device
1681  * driver to register)
1682  */
1683 fs_initcall(pcistub_init);
1684 #endif
1685
1686 #ifdef CONFIG_PCI_IOV
1687 static struct pcistub_device *find_vfs(const struct pci_dev *pdev)
1688 {
1689         struct pcistub_device *psdev = NULL;
1690         unsigned long flags;
1691         bool found = false;
1692
1693         spin_lock_irqsave(&pcistub_devices_lock, flags);
1694         list_for_each_entry(psdev, &pcistub_devices, dev_list) {
1695                 if (!psdev->pdev && psdev->dev != pdev
1696                     && pci_physfn(psdev->dev) == pdev) {
1697                         found = true;
1698                         break;
1699                 }
1700         }
1701         spin_unlock_irqrestore(&pcistub_devices_lock, flags);
1702         if (found)
1703                 return psdev;
1704         return NULL;
1705 }
1706
1707 static int pci_stub_notifier(struct notifier_block *nb,
1708                              unsigned long action, void *data)
1709 {
1710         struct device *dev = data;
1711         const struct pci_dev *pdev = to_pci_dev(dev);
1712
1713         if (action != BUS_NOTIFY_UNBIND_DRIVER)
1714                 return NOTIFY_DONE;
1715
1716         if (!pdev->is_physfn)
1717                 return NOTIFY_DONE;
1718
1719         for (;;) {
1720                 struct pcistub_device *psdev = find_vfs(pdev);
1721                 if (!psdev)
1722                         break;
1723                 device_release_driver(&psdev->dev->dev);
1724         }
1725         return NOTIFY_DONE;
1726 }
1727
1728 static struct notifier_block pci_stub_nb = {
1729         .notifier_call = pci_stub_notifier,
1730 };
1731 #endif
1732
1733 static int __init xen_pcibk_init(void)
1734 {
1735         int err;
1736
1737         if (!xen_initial_domain())
1738                 return -ENODEV;
1739
1740         err = xen_pcibk_config_init();
1741         if (err)
1742                 return err;
1743
1744 #ifdef MODULE
1745         err = pcistub_init();
1746         if (err < 0)
1747                 return err;
1748 #endif
1749
1750         pcistub_init_devices_late();
1751         err = xen_pcibk_xenbus_register();
1752         if (err)
1753                 pcistub_exit();
1754 #ifdef CONFIG_PCI_IOV
1755         else
1756                 bus_register_notifier(&pci_bus_type, &pci_stub_nb);
1757 #endif
1758
1759 #ifdef CONFIG_XEN_ACPI
1760         xen_acpi_register_get_gsi_func(pcistub_get_gsi_from_sbdf);
1761 #endif
1762
1763         return err;
1764 }
1765
1766 static void __exit xen_pcibk_cleanup(void)
1767 {
1768 #ifdef CONFIG_XEN_ACPI
1769         xen_acpi_register_get_gsi_func(NULL);
1770 #endif
1771
1772 #ifdef CONFIG_PCI_IOV
1773         bus_unregister_notifier(&pci_bus_type, &pci_stub_nb);
1774 #endif
1775         xen_pcibk_xenbus_unregister();
1776         pcistub_exit();
1777 }
1778
1779 module_init(xen_pcibk_init);
1780 module_exit(xen_pcibk_cleanup);
1781
1782 MODULE_DESCRIPTION("Xen PCI-device stub driver");
1783 MODULE_LICENSE("Dual BSD/GPL");
1784 MODULE_ALIAS("xen-backend:pci");